RT Journal Article
SR Electronic
T1 On the Role of Cortex-Basal Ganglia Interactions for Category Learning: A Neurocomputational Approach
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 9551
OP 9562
DO 10.1523/JNEUROSCI.0874-18.2018
VO 38
IS 44
A1 Francesc Villagrasa
A1 Javier Baladron
A1 Julien Vitay
A1 Henning Schroll
A1 Evan G. Antzoulatos
A1 Earl K. Miller
A1 Fred H. Hamker
YR 2018
UL http://www.jneurosci.org/content/38/44/9551.abstract
AB In addition to the prefrontal cortex (PFC), the basal ganglia (BG) have been increasingly often reported to play a fundamental role in category learning, but the circuit mechanisms mediating their interaction remain to be explored. We developed a novel neurocomputational model of category learning that particularly addresses the BG–PFC interplay. We propose that the BG bias PFC activity by removing the inhibition of cortico–thalamo–cortical loop and thereby provide a teaching signal to guide the acquisition of category representations in the corticocortical associations to the PFC. Our model replicates key behavioral and physiological data of macaque monkey learning a prototype distortion task from Antzoulatos and Miller (2011). Our simulations allowed us to gain a deeper insight into the observed drop of category selectivity in striatal neurons seen in the experimental data and in the model. The simulation results and a new analysis of the experimental data based on the model's predictions show that the drop in category selectivity of the striatum emerges as the variability of responses in the striatum rises when confronting the BG with an increasingly larger number of stimuli to be classified. The neurocomputational model therefore provides new testable insights of systems-level brain circuits involved in category learning that may also be generalized to better understand other cortico–BG–cortical loops.SIGNIFICANCE STATEMENT Inspired by the idea that basal ganglia (BG) teach the prefrontal cortex (PFC) to acquire category representations, we developed a novel neurocomputational model and tested it on a task that was recently applied in monkey experiments. As an advantage over previous models of category learning, our model allows to compare simulation data with single-cell recordings in PFC and BG. We not only derived model predictions, but already verified a prediction to explain the observed drop in striatal category selectivity. When testing our model with a simple, real-world face categorization task, we observed that the fast striatal learning with a performance of 85% correct responses can teach the slower PFC learning to push the model performance up to almost 100%.